Abstract

All-ZnO light-emitting diodes(LEDs) offer the promise of a low-cost, brighter alternative to existing GaN-based light emitters for solid-state lighting applications, in part due to the higher exciton binding energy of ZnO. We have used ISE TCAD™ simulations to examine the effect of active, - and -layer dopings and thicknesses on the optical output intensity and current-voltage characteristics of both vertical and lateral geometry ZnOLEDs. The latter geometry is attractive for ultralow structures with the ZnO deposited on glass substrates. The current density distribution is more uniform in the vertical structures but there is little difference in optical output power as a function of doping or layer thickness between the two geometries.

Received 16 December 2005Accepted 31 January 2006Published online 07 March 2006

Acknowledgments:

This research was sponsored by ARO under Grant No. DAAD19-01-1-0603, the Army Research Laboratory, NSF DMR 0400416 and 0305228, Dr. L. Hess, DOE grant DE-FC26-04NT42271, AFOSR under Grant No. F49620-03-1-0370, and DOE contract DE-AC05-00OR22725. The authors acknowledge the Major Analytical Instrumentation Center, Department of Materials Science and Engineering, University of Florida.